Asian soybean rust found in Mississippi

BATON ROUGE, La. – USDA’S Animal and Plant Health Inspection Service lab results have confirmed Asian soybean rust on three of four samples taken during a Louisiana inspection tour on Nov. 11. Results from a sample taken in southern Mississippi have also proven positive.

Of that sample, Alan Blaine, Mississippi Extension soybean specialist says the APHIS-led inspection team was taken to a 1,000-acre soybean field south of Natchez. “They climbed out of the truck and found this suspicious-looking sample right there. Nothing else was found in the whole field. What are the chances? That was like finding a needle in a haystack.”

Connecting wind patterns and sample locations (Iberia, St. John and St. Mary parishes in Louisiana) points to spores hitching a ride on Hurricane Ivan two months ago. However it got here, David Lanclos says it’s time to deal with it.

“After talking to more and more experts – guys with much more experience with soybean rust than me – there’s total confidence that the soybean industry isn’t mortally wounded, like some have been saying,” says the Louisiana Extension soybean specialist. “Those reports are just wrong.”

That’s not to say that no soybean acres will be lost, however.

“I feel, at least in the Gulf South – especially in southern Louisiana, unfortunately – soybean acres will shift to other crops,” says Lanclos. “But those shifts will be in areas where profit margins are already very, very thin.

“Bottom line: crunched numbers show that land-renting producers will need to be in the high 30-bushel to low 40-bushle range to make beans profitable. If producers own the land, obviously it would be much easier to grow beans. Unfortunately, many of these low-margin beans are grown on rented land.”

Lanclos admits that “until we can figure out how this disease behaves in the United States, we’ll be shooting at it from the hip. We’re anticipating it will behave similarly to what it does in South America. Until we know for sure, though, it’s just important not to panic. We’ll get this figured out.”

Signs of the disease were discovered on Nov. 6 by Ray Schneider, an LSU AgCenter plant pathologist, during a tour of a Baton Rouge-area research farm production field. A USDA plant pathologist says the early discovery of the disease was unusual.

"The LSU AgCenter is to be commended for diligence in finding this disease," says Russ Bulluck, an APHIS plant pathologist. "It is amazing to find this at such an early stage."

While gloomy predictions abound, there is still a small chance that rust won’t show up next year.

“If Hurricane Ivan brought this rust and dumped it only in Louisiana and Mississippi, there’s still hope,” says Billy Moore, Mississippi Extension plant pathologist emeritus. “We’ve got to make sure the kudzu (another host for the fungus) is taken out, though. Normally, the first frost kills out the kudzu. So folks should be praying for a hard freeze all the way to the Gulf Coast.”

Asian soybean rust spores can live some 50 days without a host.

“Provided there are no other host crops, we could be looking at clean fields next year,” says Moore.

If, however, the rust has found its way to balmier Florida or southern Texas, Moore says even slight hopes for a rust-free season would be dashed.

“If it’s down there,” he says, “game over.”

(Editor’s note: some information for this story was provided by the LSU AgCenter.)